package com.cmc6.websocket.config;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler;
import io.netty.handler.stream.ChunkedWriteHandler;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;

/**
 * NettyServer Netty服务器配置
 */
@Slf4j
public class NettyServer {

    @SneakyThrows
    public void start() {
        EventLoopGroup bossGroup = new NioEventLoopGroup();
        EventLoopGroup group = new NioEventLoopGroup();

        try {
            ServerBootstrap sb = new ServerBootstrap();
            sb.option(ChannelOption.SO_BACKLOG, 1024);
            sb.group(group, bossGroup) // 绑定线程池
                .channel(NioServerSocketChannel.class) // 指定使用的channel
                .localAddress(WebSocketApplicationRunnerConfig.WEBSOCKET_PORT) // 绑定监听端口
                .childHandler(new ChannelInitializer<SocketChannel>() { // 绑定客户端连接时候触发操作
                    @Override
                    protected void initChannel(SocketChannel ch) { // 绑定客户端连接时候触发操作
                        // websocket协议本身是基于http协议的，所以这边也要使用http解编码器
                        ch.pipeline().addLast(new HttpServerCodec());
                        // 以块的方式来写的处理器
                        ch.pipeline().addLast(new ChunkedWriteHandler());
                        ch.pipeline().addLast(new HttpObjectAggregator(8192));
                        ch.pipeline().addLast(new MyWebSocketHandler());
                        ch.pipeline().addLast(new WebSocketServerProtocolHandler("/ws", null, true, 65536 * 10));
                    }
                });
            ChannelFuture cf = sb.bind().sync(); // 服务器异步创建绑定
            cf.channel().closeFuture().sync(); // 关闭服务器通道
        } finally {
            group.shutdownGracefully().sync(); // 释放线程池资源
            bossGroup.shutdownGracefully().sync();
        }
    }
}
